Wellhead



l- 19150 H. ALLEN 2,517,821

WELU-IEAD Original Filed "9v. '7. 1938 3 Sheets-Sheet 1 HERBERT ALLEN lNVENTOR Aug- 8, 1950 H. ALLEN 2,517,821

IELLHEAD Original Filed Nov. 7, 1938 3 sh t -31 z Fitili m 8, 1950 H. ALLEN 2,517,821

' IELLHEAD Original Filed Nov. 7, 1938 8 3 Sheets-sheaf 3 72 ELELL- 9 FL 3.5.. HERBERT ALLEN INVENTOR rtaaaaat' a m Herbert Houston, 'lex: aadgnor to Cameron Iron Worh, Houston, Tex, a corporation Original manta-mm]... '1, 19:8, Serial No..

Divided and this-appiicationNovemher 22, 1943, Serial No. 511,255

acclaim.

This application is a division of my prior copending application for Well Head. Serial No. 239,320, filed November '7, 1938, now United Bilates Letters Patent 2,337,221 dated-December 2 1943."

This invention relates-to well heads and the like and has for its general object the provision of a means for providing a seal between a well head, a pipe hanger or the like disposed within the well head, and a bonnet or other flttingsecured to the upper end of the well head.

Various means have heretofore been provided for providing seals at the points referred to but such means have forthe most part depended upon very accurate machining and careful placing and seating of theparts in order to provide a seal. Even then, if the machined parts happ n not to be exactly accurate, or if a greater load is placed upon the hanger than that for which it was intended, or if for any other reason the hanger failed to seat at exactly-the proper point within the well head, the seal between the hanger and the bonnet above the well head or the seal between the well head and such bonnet or oth iltting would be defective.

It is, therefore, a more specific object of this invention to provide a sealing means which need -not be as accurately machined and seated as those heretofore used but which will nevertheless provide good seals between the respective parts. Another object of this invention is to provide a sealing means which will be sumciently flexible to accommodate itself to slight. deviations from V the proper or intended relative positions of the parts against which it is to seal, and will thus provide a good seal even though the parts are not. seated together in exactly the manner or to the exact extent intended.

Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawing wherein are illustrated certain embodiments of the invention. 7

In the drawing:

Fig. 1 shows a longitudinal cross section through a casing head, a tubing head, and a tubing hanger within the casing head and illustrating one form of sealing assembly constructed in accordance with this invention.

Fig. 2 is a view similar to the central portion of Fig. 1 and-illustrating a slight modification of the sealing ring shown in Fig. 1.

Fig. 3 is a view substantially the same as Fig. 2 but illustrating a still further slightly modified form of ring.

(cuss-:2) z

Hg.4isaviewsimilartoFig.2butshowinga two piece ring assembly construction.

Fig.5isavlewsimilartoFlg2butshowing the invention as applied to a structure utilizing two independent sealing rings with a part of oneofthewellheadmemberstobesealedtm gether forming a means for wedging between the two sealing rings.

Referring first to the structure illustrated in 9 Fig.- 1, the numeral I designates what may be termed the surface casing having a casing head 2 supported on its upper end. This casing head Ihastheusuallateralflowopenings3andl, and on its upper end is provided with a flange 5 by which it may be joined to the other parts of the well head equipment. This casing head 2issecuredtothesurfacecasinglb'ymeans of threads 5 or other suitable connection, and has a vertical passageway I extending entirely through the head.

Adjacent its upper end the vertical passageway I within the casing head is provided with an upwardly and outwardly tapered seat 8 adapted'to receive a casing hanger-9 whichjs likewise provided with a tapered seat ll engaging with the seat l.-- This hanger is provided adjacent its lower end with suitable threads il whereby inner casing I: may be suspended therefrom.

The upper face of the flange 5 is provided with a groove I: which may be of the usual cross section for the purpose of receiving sealing rings or may be of some other suitable cross section for receiving the appropriate part of the sealing ring beingused,

In this case the groove I3 is adapted to receive the downwardly extending flange ll of the sealingring liforthepurposeofprovidingaseal 0 between this groove l3 and the ring l5. Preferabl'y, however, the groove i3 is made of such a depth that the flange ll cannot extend clear to the bottom thereof.

The ring i5 is also provided with a radially inwardly extending portion having a part I adapted to seat against and be wedged tightly agaiimt the inclined upwardly facing seat II on the hanger 9. This ring is also provided adjacent its outermost part with a sealing surface ll adapted to be received within a relatively wide groove I! in the tubing head 20 which is seated upon the casing head 2. The flange 5 of the casingheadissecuredtoasimilarflangeon the lower end of the tubing head 20 by means of bolts 2i having nuts 22 thereon, these bolts extending through the flanges so as to hold the flanges together.

The hanger 9 may, if desired, be provided with threads 23 adjacent its upper end whereby it may be handled from above and seated by means of a seating nipple which is then disconnected and removed from the well.

The tubing head is provided with the usuallateral outlets 24 and 25 and with an upper flange 26 having bolt holes 21 therethrough for the purpose of receiving bolts similar to the bolts 2| so that additional parts may be secured thereby to the tubing head. The upper surface of this tubing head is likewise provided with the usual sealing ringgroove 28, and its inner wall has a hanger seat 29.

It will be appreciated that because of the considerable radial extent of the ring and of the fact that the radially inner parts which contactthe hanger l and the tubing head 20 are spaced a substantial distance from the radially outer parts which contact the casing head 2 and the tubing head 20, if the hanger is seated in the casing head 20 a little too far or not quite far enough. the ring would flex within itself under pressure from the bolts 2i so that the radially inner and outer sealing parts referred to might move axially slightly with respect to each other to provide sealing engagement of all of the sealing surfaces of the ring. That is to say, assuming that the hanger 9 should seat within the cas= ing head 2 further down than originally intended,

then when the ring i5 is put in place and the I tubing head 20 placed thereon, the part i6 of this ring would not be in contact with the tapered sealing surface H on the hanger. However,

when the bolts 2| are tightened, the contact be- 4 betweentheouterwallofthegroove ilsndtile outer lower sealing part on the ring would tend to force it radially inwardly and this reaction would increase the sealing eflect between the parts it and I1.

likewise, the sealing force exerted upon theupper outer part of the ring by the outer wall of the groove ll willhave its reaction on the upper inner surface of' the ring where it seals against the inner wall the groove ll. In each case. therefore, it may be said that the intermediate parts of the ring transmit the reaction from the sealing force exerted on the inner or the/outer sealingparts'oftherlngtotheouterortheinner parts as the case may be so that the sealing force appliedtoonesealingpartwilllikewisebeapplied to the other.

In Fig. 2 there is'iilustrated a modified-form ofsealingringinplsceontheupperendsurface of a casing head II or the like. This casing head isshownashavingailangeil onitsupperend and a tapered seat 32 on its inner surface adjacent its upper end, this seat being adapted to receive the tapered lower end portion 33 of the hanger II. This hanger 84 is threaded at its lower end 3! to receive a casing and at its upper end as at I to receive a landing nipple or the like. Y

Theupper surface of the flange II is provided with snannular groove 31 adapted to receive the lower flange'like part II on the sealing ring 3!. This'sealing ring is for the purpose of providingaseal betweentheflangell onthecasing head II and theflange II on a tubing head 4! or the like. These are connected by means of bolts 12 having nuts l3. thereon so that they tween the tubing head 20 and the radially inner part of the ringwould cause the ring to flex, its cross section in substance rotating upon the seat of the flange ll within the groove l3. This will naturally produce a movement of the radially inner part of the ring axially downwardly while] on the ring at all points. Likewise, if the hanger I should seat within the casing head before it is as far down in the casing head as originally intended, the ring I5 would then be supported on the ring seat I! of the hanger and the flange or projection it would not be in sealing engagement with the groove l3. However, when force is applied to the lower flange of the tubing head 20 by means of the bolts 2i, the outer sealing parts of the ring would be forced downwardly while the inner sealing parts remain at the same level, the ring being thus flexed and its cross section rotated about its seat on the hanger until the flange ll comes into sealing engagement with the groove II. 1

It is further to be noted that the forced engagement between the part ii of the ring and the part II on the hanger by tightening the bolts 2| would tend to expand radially this inner sealing part of the ring and that the reaction from this sealing force would be transmitted through the intermediate portion of the ring to the outer sealing part It, pressing this outer sealing partv radially outwardly against the outer wall of the may be tightened and the flange ll having a groove 44 in its lower surface for the purpose of receiving the upwardly projecting sealing flange II on the ring 3|.

This ring a also'has a radially inwardly procontactwith a tapered seat 41 on the hanger, 34

and the upper portion of which is adapted to provide sealing contact with a similar seat It on the tubing head ll.

In operation the form shown in Fig. 2 is very similar to that illustrated in Fig. 1 but with the addition of the flange 45 which provides a some what more positive form of seal with the flange ll. In this M; which is of T-shaped cross section the outer surfaces of the flange parts 38 and 45 provide a radially outer sealing part adapted toformaseal with respecttothe flanges SI and ll respectively, whereas the. inner curved portion 46 of the ring-provides an inner part adapted to form a seal between the flange 40 and the hanger 34, as in the previously described form. The inner sealing parts on the ring and the outer sealing parts on the ring engage tapered surfaces I in forming their seals and the intermediate portions of the ring transmit the forces thus applied to the inner andouter sealing parts so that the reaction from each is transmitted to the other.- Also, any inaccuracy or defect which might cause improper seating of the sealing parts will tend to cause the ring to be distorted with the inner and outer sealing parts moving axially with respect to each other and a perfect seal is formed at all points.

In Fig. 3 thecasing head I. is provided with an upper flange 5| similar to those shown in the previously described forms of the invention, and on its innersurface is provided with a tapered like.

The upper face of the flange 58 is provided with 'an inwardly and downwardly tapering inner Seating surface 58 adapted to receive the outer and lower sealing part 61 on the sealing ring 58.

The inner and lower sealing part 58 of this sealing ring 58 is adapted to seat against the tapered surface 68 provided on the upper end of the hanger 58 so that when the ring is pushed downwardly it will tend to wedge itself between the surfaces 56 on the flanges 58 and 68 on the hanger 53 and the reaction from the sealing force on each of these surfaces will be transmitted through the intermediate portion of the ring to the other surface thus equalizing the sealing forces on these two inner and outer parts of the ring.

The upper portion 6| of the ring is adapted to seat within the groove 62 formed in the lower face of the flange 63 on a tubing head 64 or the like. These flanges 58 and 68 are secured together by means of bolts 65 having nuts 66 on their ends.

It will be seen that the outer sealing portions groove 82 has tapered opposite side adapted to receive the curved outerportions of the rings formed by the outer, upper and lower parts of the sealing ring will engage against the tapered sealing surfaces on the respective flanges 58 and 63 as these flanges are pulled together, At the same time, theupper and lower inner surfaces of the ring will be wedged against the correspondingly tapered surfaces on the flange 63 and the upper end of the hanger 53. In each case the sealing forces applied to the inner sealing parts of the ring will be transmitted by the intermediate portions of the sealing ring to the outer sealing parts thereof and vice versa, thus substantially equalizing all of the sealing forces on the various sealing 'parts of the ring. At the same time, becausethe inner sealing parts and the'outer sealing parts are substantially spaced from each other, any inequality or inaccuracy in the seating surfaces which might tend to prevent the inner or the outer sealing parts of the ring from properly seating will be overcome by the flexure of the ring so that the inner and outer parts of the ring may move axially relative to each other and permit the ring properly to seat.

In Fig. 4 the casing head 61 is provided with an upper flange 68 and with an inner tapered shoulder 68 therein adapted to receive the tapered shoulder I8 on the hanger II. As in the previously described structures the hanger II is provided with a lower threaded part I2 adapted to be connected to the upper end of a casing or the like and with an upper threaded part I3 adapted to receive a landing nipple or the like.

The upper surface of the flange 68 has a sealing ring groove 16 therein adapted to receive the lower flange likepart I5 of the outer sealing ring "I6. There is also an inner sealing ring 11 which is complementary to the outer sealing ring I6 and which has an outwardly projecting part I8 in contact with a corresponding part of the ring 16. This inner sealing ring 11 also has a downwardly projecting flange like part I8 adapted to be seated within a groove88 formed in the upper end surface of the hanger I I.

The upper surfaces of the rings I6 and I1 complement each other to provide a composite ring of arcuate configuration as shown at 8| adapted to flt within the broad ring groove 82 in the flange 88 of a tubing head 84 or the like. This broad I6 and I1 respectively.

Itwill be seen that the rings I6 and 11 provide outer and inner sealing parts respectively and that in the event the hanger should seat a little higher or a little lower than shown the inner sealing ring I1 might move upwardly or downwardly with respect to the casing head 61 in order that it might properly seat within the groove 88. It will readily be seen that this would not interfere with the seating of the outer upper surface of the ring 16 against the sloping side wall of the groove 82 nor with the seating of the inner upper surface of the ring II against the inner sloping side wall of the groove 82. Furthermore, the sealing force exerted between the curved outer sur face of the ring 11 and the sloping side wall of the groove 82 will be transmitted through the contacting portions I8 of the two rings to the ring 11 and caused to produce a further sealing effect between the curved surface of the ring 11 and the inner sloping wall of the groove 82.

Referring finally to the form illustrated in Fig. 5, the casing head or the like is substantially the same as illustrated in Fig. 4 being provided with a flange 86 and with a tapered shoulder 81 on its inner surface. This tapered shoulder receives the tapered seat 88 on the hanger 88,'which hanger has a threaded lower portion 88 to receive a casing and a threaded upper portion 8| to receive a handling nipple.

The upper surface of the flange 86 is provided with a groove 82 to receive a sealing ring 88 of conventional cross section. The hanger 881s also provided with a sealing ring groove 84 adapted to receive a second sealing ring 85 of smaller diameter than the first sealing ring 83. The upper parts of these two sealing rings are adapted to seat within grooves which are cut deeply and tapered toward each other as shownat 86 and 81 respectively. This formation of these grooves leaves a portion 88 between the two rings for transmittin forces from one to the other and balancing the sealing forces between them. This part 98 is left joined by a means of a narrow zone of material 88 between the bottoms of the grooves to the body of the flange I88 on the tubing head I 8 I. These flanges 86 and I88 are joined together and held in place by means of bolts I82 having nuts I83 thereon.

Just as, in the case of the form shown in Fig. 4 the outer ring I6 provides an outer sealing part forming a seal between the flange 68 and the flange 83, so in the form shown in Fig. 5 the outer ring 83 provides a seal between the lower flange 86 and the upper flange I88. Also, just as the inner ring 11 in Fig. 4 provides an inner sealing part forming a seal between the hanger II and the flange 83, just so the inner ring 85 forms an inner sealing part providing a seal between the hanger 88 and the flange I88. These two rings each form a seal with respect to the flange I88 against the tapered outer or the tapered inner surface of the groove 86 or 81 as the case may be. Were it not for the presence of the part 88, the upper portions of these rings would be forced toward each other, but the part 88 serves to transmit force from one to the other so that the reaction from the force with which one is sealed is transmitted to the other to assist in forming a seal with such other ring.

If it should happen that the hanger 88 seats a little lower than intended within the head 85, then, of course, the ring 85 will be lower with respect to the flange I00. However, this will not interfere with the making of a proper seal because it will only mean that the flange Ill may be pushed a little lower with respect to the ring 83 thus moving the upper portion of this ring in a radially inward direction, causing a movement of the part 98 with respect to the flange I", this movement being toward the inner ring 95 until the inner ring 95 is contacted and forced into sealing engagement with the inner surface of the roove 91.

From the foregoing it will be appreciated that in all of the various forms illustrated a sealing assembly is provided in which there are what might be termed inner and outer sealing parts so arranged that if the hanger does not seat at exactly the place intended within the casing head, the outer and inner sealing parts of the assembly may move axially with respect to each other to make up the difference. At the same time there is provided in each instance a means for balancing the outer and inner forces against each other through means which is interposed between the outer and inner sealing parts, so that the axial movement of the outer and inner sealing parts with respect to each other will not prevent the making of a proper seal by each oi the sealing parts.

A means has thus been provided for carrying out and accomplishing all of the objects and advantages sought by this invention.

Having described my invention, I claim:

1. A ring sealing assembly to provide a seal between two annular members and a third annular member within one of said two members, including a seal ring to contact one of the members and the second member, a seal ring to contact the second of the members and the third member, and means forming a part of the assembly and adapted to be wedged between the two seal rings to force them into tighter sealing engagement.

2. A packing connection for providing a seal between two annular members and a third annular member within one of said two members, comprising an annular ring sealing means having a radially outer annular part with surfaces adapted to provide sealing engagement with each of two of said members, and a radially inner annular part having surfaces adapted to provide sealing engagement with one of said two members and the third member, said outer and inner annular parts being movable relative to each other in an axial direction, and means in addition to and between said inner and outer parts and movable with respect to said members whereby the reaction from the sealing force exerted on one of said parts will be transmitted to the other to assist in sealing such other part.

3. A packing connection for providing a seal I between two annular members and a third annular member within one of said two members, comprising an annular ring sealing means having a radially outer annular part with surfaces adapted to provide sealing engagement with each of two of said members, and a radially inner annular part having surfaces adapted to provide sealing engagement with one of said two mem bers and the third member, said outer and inner annular parts being movable relative to each other in an axial direction, and means in addition to and between said inner and outer parts and movable with respect to said members whereby the reaction from the sealing force exerted on one of said parts will be transmitted to the other to assist in sealing such other part, said 8 innerandouterpartsandsaidmeansbeingin the form of one integral annular ring.

4. A packing connection for providing a seal between two annular members and a third annular member within one of said twomembers, comprising an annular ring sealing means having a radially outer annular part with surfaces adapted to provide sealing engagement with each of two of said members and a radially inner annular part having surfaces adapted to provide sealing engagement with one of said two members and the third member, said outer and inner annular parts being movable relative to each other in an axial direction, and means in addition to and between said inner and outer parts and movable with respect to said members whereby the reaction from the sealing force exerted onone ofsaidpartswillbetransmittedtothe other to assist in sealing such other part, said inner and outer parts being formed on separate annular rings.

5. A packing connection for providing a seal between two annular members and a third annular member within one of said two members including an annular ring sealing assembly having a radially outer annular part with surfaces adapted to provide sealing engagement with each of two of said members and a radially inner annular part having surfaces adapted to provide sealing engagement with one of said two members and the third member, said outer and inner annular parts being movable relative to each other in an axial direction, and means in addition to and between said inner and outer parts and movable with respect to said members whereby 'the reaction from the sealing force exerted on one of said parts will be transmitted to the other to assist in sealing such other part, said means being formed integrally with one of said members.

6. A packing connection for providing a seal between two annular members and a third annular member within one of said two members, comprising an annular ring sealing means having a radially outer annular part with sin-faces adapted to provide sealing enga ment with each of said two members, and a radially inner annular part having surfaces adapted to provide seating ngagement withpne of said two members and the third member, said outer and inner parts being movable relative toeach other in an axial direction, and means in addition to and between said inner and outer parts and movable with to said members whereby the reaction from the sealing force exerted on one of said partswillbetransmittedtotheothertoassist in sealing such other part, said last mentioned means being flexibly joined to one of said memhere.

7. In combination, a first annular member having a groove therein, a second annular memberopposedtotheflrstandhavingonegroove therein registering with the groove in the first member and a second groove smaller than said one groove, said grooves in the second member being cut deeply-and inclined toward each other to provide a surface portion between them flexibly joined to the body of the second member, a third annular member within the first member and underlying that portion of the second member having a smaller groove therein and said third member having a groove therein registering with the smaller groove in the second member,alargersealingringextendingintothe groove in the first member and the larger groove V thesmallergrooveinthesecondmember,and means for urging said members together to tighten said rings insaid grooves and provide seals between said members.

8. In combination, a pair of annular members andathirdannularmemberwithinoneofsaid two members, and a connection for providing a seal between said three annular members, said connection comprising an annular ring sealing means having a radially outer annular part with surfaces adapted to provide sealing engagement with each of two of said members, and a radially inner annular part having surfaces adapted to provide sealing engagement with one of said two members and the third member, said outer and inner annular parts being movable relative to each other in an axial direction, and means in addition to and between said inner and outer parts and movable with respect to said members whereby the reaction from the sealing force exertedononeofsaidpartswillbetransmitted totheothertoassistinsealingsuchotherpart, said members respectively having tapering surfaces adapted to receive the radially outer annularpartofsaidringsealingmeansandoppositely tapered surfaces adapted to receive the radiallyinnerannularpartofsaidringsealing means, whereby said outer and inner paris of the ringsealingmeanswillbeforcedtowardeach other when said members are pulled toward each other, and means for forcing said members toward each other.

9. A packing connection for providing a seal' between two annular members and a third annular member within one of said two members, comprising an annular ring sealing means having a radially outer'annular part with surfaces adapted to provide sealing engagement with each of two of said members, and a radially inner annular part having surfaces adapted to provide sealing engagement with one of said two memhead groove and said shoulder, and an adapter bers and the third member, said outer part having an axially extending flange-like portion engaging one of said members and said outer and inner annular parts being movable relative to each other in an axial direction, and means in addition to and between said inner and outer parts and movable with respect to said members whereby the reaction from the sealing force exerted on one of said parts will be transmitted to the other to assist in sealing such other part, said inner and outer parts and said means being in the form of one integral annular ring.

10. A packing connection for providing a seal between two annular members and a third annular member within one of said two members, comprising an annular ring sealing means having a radially outer annula part with surfaces adapted to provide sealing engagement with each of two of said members, and a radially inner annular part having surfaces adapted to provide sealing'engagement with one of said two members and the third member, said outer part comprising an axially extending flange-like portion projecting in each direction from the body of said annular ring sealing means and engaging two of said members, and said outer and inner annular parts being movable relative to each other in an axial direction, and means in addition to and between said inner and outer parts and movable with respect to said members whereby the reaction from the sealing force exerted on one of said sealing such other part, said inner and outer and said means being in the form of one integral annular ring.

11. A casing and tubing seal for wells including a well head, a hanger seated therein, a groove in said head; a shoulder on said hanger, a hold down member, a groove therein spanning said head groove and said shoulder, and an adapter ring shaped in cross section to fit in both sides of the spanning groove, against said shoulder and in said head groove so as to'seal both said head and hanger.

12. A'casing and tubing seal for wells including a well head, a-hanger seated therein, a groove in said head, a shoulder on said hanger, a hold down member, a. groove therein spanning said ring shaped in cross-section 'to fit in both sides of the spanning groove, against said shoulder and in said head groove so as to 'seal both said head and hanger, saidring being substantially T- shaped.

13. A casing and tubing seal for wells including a casing head, a hanger sealed therein, said head and said hanger each having an upwardly facing groove therein, a hold down member hav-' ing a downwardly facing groove therein spanning said head and hanger grooves, and a pair of abutting adapter rings each having a leg, the leg of one being in the head groove. the leg of the other being in the hanger groove, and a face on each ring to engage an edge of said spanning groove.

14. A casing and tubing seal for wells including a casing head, a hanger, an upwardly facing groove in each said head and hanger, a. hold down member, a pair of spaced slots therein defining a depending tongue portion, a seal ring in each said head and said hanger grooves, one of said'rings.

= projecting into each of said slots, and means to clamp said member to said headto wedge said tongue against said rings, said tongue being moveable tov equalize the pressure on said rings.

15. A casing and tubing seal for wells including a well head having a groove therein, a hanger seated in said head, a shoulder on said hanger. a hold down member having a groove therein spming said head groove and said shoulder, and a composite adapter ring formed of a plurality of parts and having an ag regate cross section to fit in both sides of the spanning groove, against said shoulder, and in said head groove'so as to seal both said head and hanger.

16. A casing and tubing seal for wells including a well head, a hanger seated therein, an inclined radially inwardly facing surface on said head, an inclined radially outwardly facing surface on said hanger, a hold down member, opposed radially outwardly and inwardly facing inclined surfaces on said hold down member, and an adapter ring having parts adapted to seal against each of said inclined surfaces respectively.

radially inwardly facing seat on said head, an inclined radially outwardly facing seat on said hanger, a hold down member, opposed inclined radially inwardly and outwardly facing seats on said hold down member, and a composite adapter ring comprising inner and outer parts capable of relatively axial movement and having an aggregate cross section shape providing parts adapted to seal against said inclined seats re pectively.

18. A casing and tubing seal for wells includin parts will be transmitted to the other to assist'in 7 a well head, a hanger seated therein, an inclined radially inwardly facing seat on said head, an

inclined radially outwardly facing seat on said hanger, a hold down member, opposed inclined radially inwardly and outwardly facing seats on said hold down member, and an adapter ring of one piece and flexible to permit relative axial movement of its radially inner and outer extremities andhaving parts on its radially inner and outer extremities adapted to seal against said inclined seats respectively.

19. In a packing connection between three annular members, one of which is located at least in part within one of the others, said members having seating surfaces arranged about a common axis adapted to receive sealing material therebetween, the improvement which resides in the combination therewith of annular seal means having concentric, spaced apart, inner and outer pairs of sealing surfaces, one of the surfaces of each of said pairs of surfaces adapted to engage the corresponding seating surfaces of one of the members and the other surfaces of said pairs of surfaces adapted to engage corresponding seating surfaces on the other two members respectively, the inner and outer pairs of surfaces being' slightly movable relatively to each other in an axial direction to provide for engagement of the ant sealing surfaces within the corresponding seating flexibly maintained in radially spaced relation to each other.

20. A packing connection for providing a seal between two annular members and a third annular member within at least one of said two members, comprising an annular ring sealing means having a radially outer pair of annular surfaces adapted to provide sealing engagement with each of two of said members, and a radially inner pair of annular surfaces adapted to provide sealing engagement with one of said two members and the third member, said outer and inner annular pairs of surfaces being slightly movable relative to each other in an axial direction, and means in addition to and between said inner and outer pairs of surfaces and movable with respect to said members whereby the reaction from the sealing force exerted on one of said surfaces of one pair will be transmitted to one of the surfaces of the other pair to assist in sealing such other pair.

- HERBERT ALLEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,083,089 Rector July 8, 1937 2,083,090 Rector July 8, 1937 2,087,179 Barker July 13, 1937 2,104,180 Barker Jan. 4, 1938 2,337,221 Allen Dec. 21, 1943 

